American Standard TGBWF090A93AVA Installation Manual page 40

If the boiler does not light, refer to the Troublshooting
section of the Service Facts, shipped with the boiler.
4. Clock the gas meter with the boiler operating
(determine the dial rating of the meter) for one
revolution.
5. Match the "Sec" column opposite the number
of seconds checked in Table 13.
6. Read the "Flow" column opposite the number
of seconds clocked.
7. Use the following factors if necessary:
For 1 Cu. Ft. Dial Gas Flow CFH =
Chart Flow Reading /2
For 1/2 Cu. Ft. Dial Gas Flow CFH =
Chart Flow Reading /4
For 5 Cu. Ft. Dial Gas Flow CFH =
10X Chart Flow Reading /4
8. Multiply the fi nal fi gure by the heating value
of the gas obtained from the utility company
and compare to the nameplate rating. This
must not exceed the nameplate rating.
9. Changes can be made by adjusting the mani-
fold pressure. To adjust the manifold pressure:
a) Turn off all electrical power to the
boiler and close the manual On/Off gas
valve.
b) Open outlet pressure port located
in gas valve. (To open valve, use a
screwdriver). See Figure 60.
c) Attach fl exible tubing from manometer
to the gas valve outlet pressure port. See
Figure 61.
d) Remove the regulator adjustment
screw cap on the gas valve for manifold
pressure adjustment. See Figures 26 and
62.
e) Open the manual On/Off gas valve and
turn on the electrical power to the boiler.
Energize gas valve by setting thermostat
above room temperature.
f) Adjust manifold gas pressure, as
needed, to achieve desired input capacity.
To accomplish this, turn the adjustment
screw clockwise to increase the gas fl ow
rate and counterclockwise to decrease the
gas fl ow rate using an fl at-head screwdri-
ver. See Figure 62.
g) The fi nal manifold pressure setting
shall be 3" W.C.
h) Close manual On/Off gas valve.
i) Remove the manometer fl exible tubing
from outlet pressure port and close the
outlet pressure port using a screwdriver.
j) Replace the regulator adjustment screw
cap and tighten securely.
k) Open manual On/Off gas valve and
then turn on electrical power to the boiler.
l) Using a soap solution, check for gas
leaks at the pressure ports and manifold
adjustment cover.
18-CG01D1-4
40
▲ ▲
SAFETY HAZARD
REPLACE AND/OR TIGHTEN ALL PLUGS REMO-
VED WHEN ADJUSTING GAS PRESSURE. LEAK
CHECK THE FITTING BEFORE PLACING THE
BOILER INTO REGULAR SERVICE. FAILURE
TO FOLLOW THIS WARNING COULD RESULT
IN FIRE, EXPLOSION, OR PROPERTY DAMAGE.
IMPROPER INSTALLATION, MAINTENANCE
OR SERVICING COULD RESULT IN SERIOUS
INJURY, DEATH, OR PROPERTY DAMAGE.
For LP gasses, the fi nal manifold pressure setting
shall be 10.6" W.C. with an input of no more than the
nameplate rating and not less than 93% of the name-
plate rating, unless the unit is derated for altitude.
▲ ▲
CAUTION
!
If, after correctly carrying out the lighting procedure,
the burners do not light and the pushbutton light
comes on, wait about 15 seconds and then press the
abovementioned pushbutton. The reset controller
will repeat the ignition cycle. If the burners do not
light after the second attempt, consult paragraph the
"Troubleshooting" section in the Service Facts.
Boiler switch 6 has 3 positions, "0-1-TEST"; the fi rst
two have the on-off function, the third (unstable)
must only be used for service and maintenance
purposes (see wiring diagrams).
▲ ▲
!
In case of an electrical power failure while the boiler
is working, the burners will go out and re-ignite
automatically when power is restored.
Re-verify the operation of the automatic vent damper
three times with the boiler operating controls for proper
sequence. The damper must be in the open position
before combustion takes place. The damper must be in
the open position when the main burners are on. The
gas valve must be closed before the damper begins its
return to the closed position.
Determine that the water pump(s) are operating
properly.
Test low water cutoffs, automatic feed controls, pressure,
and temperature limit controls, and relief valves to
determine they are in operating condition.
WARNING
!
CAUTION